Greater Intensity Research Articles

Executive functions and behavioral economic demand for cannabis among young adults: Indirect associations with cannabis consumption and cannabis use disorder.

Behavioral economic demand for cannabis is robustly associated with cannabis consumption and cannabis use disorder (CUD). However, few studies have examined the processes underlying individual differences in the relative valuation of cannabis (i.e., demand). This study examined associations between executive functions and cannabis demand among young adults who use cannabis. We also examined indirect associations of executive functions with cannabis consumption and CUD symptoms through cannabis demand. Young adults (N = 113; 58.4% female; mean age 22 years) completed a Marijuana Purchase Task. Participants also completed cognitive tasks assessing executive functions (set shifting, inhibitory control, working memory) and semistructured interviews assessing past 90-day cannabis consumption (number of grams used) and number of CUD symptoms. Poorer inhibitory control was significantly associated with greater Omax (peak expenditure on cannabis) and greater intensity (cannabis consumption at zero cost). Poorer working memory was significantly associated with lower elasticity (sensitivity of consumption to escalating cost). Lower inhibitory control was indirectly associated with greater cannabis consumption and CUD symptoms through greater Omax and intensity, and poorer working memory was indirectly associated with greater cannabis consumption and CUD symptoms through reduced elasticity. This study provides novel evidence that executive functions are associated with individual differences in cannabis demand. Moreover, these results suggest that cannabis demand could be a mechanism linking poorer executive functioning with heavier cannabis use and CUD, which should be confirmed in future longitudinal studies. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Identification of Unique Fragmentation Patterns of Fentanyl Analog Protomers Using Structures for Lossless Ion Manipulations Ion Mobility-Orbitrap Mass Spectrometry.

The opioid crisis in the United States is being fueled by the rapid emergence of new fentanyl analogs and precursors that can elude traditional library-based screening methods, which require data from known reference compounds. Since reference compounds are unavailable for new fentanyl analogs, we examined if fentanyls (fentanyl + fentanyl analogs) could be identified in a reference-free manner using a combination of electrospray ionization (ESI), high-resolution ion mobility (IM) spectrometry, high-resolution mass spectrometry (MS), and higher-energy collision-induced dissociation (MS/MS). We analyzed a mixture containing nine fentanyls and W-15 (a structurally similar molecule) and found that the protonated forms of all fentanyls exhibited two baseline-separated IM distributions that produced different MS/MS patterns. Upon fragmentation, both IM distributions of all fentanyls produced two high intensity fragments, resulting from amine site cleavages. The higher mobility distributions of all fentanyls also produced several low intensity fragments, but surprisingly, these same fragments exhibited much greater intensities in the lower mobility distributions. This observation demonstrates that many fragments of fentanyls predominantly originate from one of two different gas-phase structures (suggestive of protomers). Furthermore, increasing the water concentration in the ESI solution increased the intensity of the lower mobility distribution relative to the higher mobility distribution, which further supports that fentanyls exist as two gas-phase protomers. Our observations on the IM and MS/MS properties of fentanyls can be exploited to positively differentiate fentanyls from other compounds without requiring reference libraries and will hopefully assist first responders and law enforcement in combating new and emerging fentanyls.

Emotion dynamics in current and remitted depression: an ecological momentary assessment study.

Individuals in a depressive episode and healthy controls exhibit robust differences on affect dynamics captured with ecological momentary assessment (EMA). However, few studies have explored affect dynamics in individuals in remission from depression, and results have been mixed. A community sample of 18-year-olds (N = 345) completed diagnostic interviews and EMA probing emotions and low interest/motivation 5× daily for 2 weeks. Affect home base, variability, and inertia were compared across currently depressed, remitted, and never-depressed groups. Both depression groups had a higher negative affect (NA) and low interest/motivation home base, lower positive affect (PA) home base, greater variability of NA, PA, and low interest/motivation, and greater NA and low interest/motivation inertia than never-depressed participants. Additionally, the currently depressed group had a higher sad home base specifically, greater variability across most negative emotions and low interest/motivation, and greater low interest/motivation inertia than the remitted group. The currently depressed and remitted groups did not differ in anxious, upset, or PA home base, anxious or PA variability, and inertia of all negative emotions and PA. Findings suggest that a number of abnormalities in emotion and reward functioning persist after a depressive episode resolves, however, the tendency to experience higher levels of sadness, greater range of a variety of negative emotions, and more variable and persistent low interest/motivation are exacerbated during depressive episodes. Conversely, greater intensity and persistence of some negative emotions (anxiety, upset) and blunted positive emotions appear to equally characterize depression in both the symptomatic and remitted state.

Patent protection, externalities, and income inequality

AbstractThis paper develops a Schumpeterian growth model with considering consumption and leisure externalities. The main purpose of this study is to investigate the effect of patent protection policy on growth and inequality, as well as the interaction between policy effect and externalities. According to the log form utility function specification, this means that the elasticity of intertemporal substitution is unity. The following are the key findings of this paper. Patent protection policy encourages innovation and increases employment in the R&D industry, which enhances economic growth while increasing income inequality. In regard to externalities, an increase in the degree of consumption (leisure) externalities results in a higher (lower) growth rate and more (smaller) income inequality. When consumption (leisure) externality is greater intensity, the growth effect of patent protection policy becomes stronger (weaker), while its influence on expanding income inequality lessens (enhances). Finally, both the Pareto optimal patent protection policy and the optimal patent policy under the maximization of social welfare positively correlate with consumption externalities, but negatively correlate with leisure externalities.

Catcalls: exotic cats discriminate the voices of familiar caregivers.

The ability to differentiate familiar from unfamiliar humans has been considered a product of domestication or early experience. Few studies have focused on voice recognition in Felidae despite the fact that this family presents the rare opportunity to compare domesticated species to their wild counterparts and to examine the role of human rearing. We tested whether non-domesticated Felidae species recognized familiar human voices by exposing them to audio playbacks of familiar and unfamiliar humans. In a pilot study, we presented seven cats of five species with playbacks of voices that varied in familiarity and use of the cats' names. In the main study, we presented 24 cats of 10 species with unfamiliar and then familiar voice playbacks using a habituation-dishabituation paradigm. We anticipated that human rearing and use of the cats' names would result in greater attention to the voices, as measured by the latency, intensity, and duration of responses regardless of subject sex and subfamily. Cats responded more quickly and with greater intensity (e.g., full versus partial head turn, both ears moved versus one ear twitching) to the most familiar voice in both studies. They also responded for longer durations to the familiar voice compared to the unfamiliar voices in the main study. Use of the cats' name and rearing history did not significantly impact responding. These findings suggest that close human contact rather than domestication is associated with the ability to discriminate between human voices and that less social species may have socio-cognitive abilities akin to those of more gregarious species. With cats of all species being commonly housed in human care, it is important to know that they differentiate familiar from unfamiliar human voices.

Examining Demand and Substitutability of Usual Brand Little Cigars/Cigarillos and Cigarettes in Young Adults Who Dual Use.

Cigarette and little cigar/cigarillo (LCC) dual use is popular among young people and poses a substantial health risk. What remains unclear is the abuse liability of LCCs vs. cigarettes, LCCs' substitutability for cigarettes, and the influence of flavors on the abuse liability and substitutability of LCCs. Sixty-five young adults (18-34 years) who dual use completed hypothetical purchase tasks to measure consumption of usual brand cigarettes and LCCs in 24 hours at increasing prices (demand), and LCC consumption at increasing cigarette prices (substitution). Three demand indices were calculated from raw data: breakpoint (price after which consumption reaches 0), Omax (maximum daily expenditure), and Pmax (price at maximum expenditure). Two indices were estimated using nonlinear mixed-effects modeling: intensity (consumption when free) and price-sensitivity (rate of decline in consumption as price increases). Substitution, and associations of flavored use with demand and substitution, were estimated using linear mixed models. Results indicated similar abuse liability for LCCs and cigarettes. Intensity was greater for cigarettes, but price-sensitivity was similar. Flavored LCC use was associated with lower price-sensitivity and greater intensity than unflavored. LCCs were significant substitutes for cigarettes, but the effect was small. Flavored use was not associated with substitution. Among young adults who dual use, LCCs and cigarettes had similar abuse liability, and those who used flavored had higher demand for their LCCs. A flavored cigar ban, as well as targeted prevention and cessation services for those who smoke flavored LCCs, may be important for reducing dual use in young adults. Cigarette and LCC dual use remains high among young adults. Using hypothetical purchase tasks with young adults who dual use, LCCs had abuse liability similar to cigarettes, but were only modest substitutes for cigarettes. Participants who used flavored LCCs reported greater abuse liability than those who used unflavored, but not greater substitution for cigarettes. Prevention and cessation services are needed to target LCCs in young people, particularly those smoking flavored products. A flavored cigar ban may help to reduce their demand.

Goliath is not the enemy: Fiddler crab species of similar size are stronger competitors than their larger adversaries in the climate change context

Many intertidal species are expanding their distribution limits towards the poles as a consequence of increased temperature due to climate change. At the same time, some intertidal habitats have been reduced due to rising sea levels. Fiddler crabs inhabit mangroves, and different species occupy well-established zones. Due to the restricted mangrove areas and consequent latitudinal expansion of the species, the distribution and density of fiddler crabs may be subject to change. The overlap forces several species to cohabit in a smaller territorial space. Fiddler crab species can vary in size, which could decisively affect territorial competition. Using Leptuca urguayensis as a reference, we tested how competing species of different sizes (larger size: L. thayeri and Minucapanema; similar size: L. cumulanta and L. leptodactyla) might interact in future climate change scenarios. First, we showed that within the territory of L. uruguayensis, the species L. cumulanta and L. thayeri occurred mainly in the lower mesolittoral zone, while L. leptodactyla and M.panema predominated in the upper mesolittoral zone. In a laboratory experiment, we evaluated whether the density and size of the heterospecific competitors could alter the agonistic behavior of Leptuca uruguayensis. Our results indicated that increasing the density can increase the agonistic behavior of L. uruguayensis with a greater intensity against species of a similar size. In a second field experiment, we demonstrated that the presence of a burrow enhances the intensity of agonistic interactions between L. uruguayensis and species of similar size. Therefore, in a scenario of territorial expansion of fiddler crabs due to climate change, it is expected that similarly sized species represent a greater competitive threat to populations of L. uruguayensis.

Sexualized culture on livestreaming platforms: a content analysis of Twitch.tv

The Twitch.tv livestreaming platform, with 3 million daily viewers internationally, has become a space for online digital culture and entertainment. Given the current concern regarding the exposure of sexualized content on social networks and its consequences for adolescence, the objective of this study is to analyze, from a gender perspective, whether women become more sexualized than men during their livestreams. Using a content-analysis design, an ad-hoc scale was developed to analyze the frequency and intensity of sexualization based on context variables and streamers’ behavior such as clothing, posture, or evocation of a sexual act, among others. After analysis of the livestreams (n = 1920), our scale made it possible to distinguish three levels of intensity: non-sexualized, sexualized, or hypersexualized. Statistically significant evidences was found in the level of sexualization between men and women in different categories of livestreaming. The results show that women are self-sexualized more and in greater intensity than men; there are also differences in the behavior and context of their livestreams. The sexualized representation of women in the media shapes gender attitudes, dehumanizes women, and legitimizes violence against them, and so it is essential to understand the role of media platforms in self-sexualization and the consequences to show women as sexual objects, principally for young people.

Sex- and age-dependent susceptibility to ventricular arrhythmias in the rat heart ex vivo

The incidence of life-threatening ventricular arrhythmias, the most common cause of sudden cardiac death (SCD), depends largely on the arrhythmic substrate that develops in the myocardium during the aging process. There is a large deficit of comparative studies on the development of this substrate in both sexes, with a particular paucity of studies in females. To identify the substrates of arrhythmia, fibrosis, cardiomyocyte hypertrophy, mitochondrial density, oxidative stress, antioxidant defense and intracellular Ca2+ signaling in isolated cardiomyocytes were measured in the hearts of 3- and 24-month-old female and male rats. Arrhythmia susceptibility was assessed in ex vivo perfused hearts after exposure to isoproterenol (ISO) and hydrogen peroxide (H2O2). The number of ventricular premature beats (PVBs), ventricular tachycardia (VT) and ventricular fibrillation (VF) episodes, as well as intrinsic heart rate, QRS and QT duration, were measured in ECG signals recorded from the surfaces of the beating hearts. After ISO administration, VT/VFs were formed only in the hearts of males, mainly older ones. In contrast, H2O2 led to VT/VF formation in the hearts of rats of both sexes but much more frequently in older males. We identified several components of the arrhythmia substrate that develop in the myocardium during the aging process, including high spontaneous ryanodine receptor activity in cardiomyocytes, fibrosis of varying severity in different layers of the myocardium (nonheterogenic fibrosis), and high levels of oxidative stress as measured by nitrated tyrosine levels. All of these elements appeared at a much greater intensity in male individuals during the aging process. On the other hand, in aging females, antioxidant defense at the level of H2O2 detoxification, measured as glutathione peroxidase expression, was weaker than that in males of the same age. We showed that sex has a significant effect on the development of an arrhythmic substrate during aging. This substrate determines the incidence of life-threatening ventricular arrhythmias in the presence of additional stimuli with proarrhythmic potential, such as catecholamine stimulation or oxidative stress, which are constant elements in the pathomechanism of most cardiovascular diseases.

The growing inadequacy of an open-ended Saffir–Simpson hurricane wind scale in a warming world

Global warming increases available sensible and latent heat energy, increasing the thermodynamic potential wind intensity of tropical cyclones (TCs). Supported by theory, observations, and modeling, this causes a shift in mean TC intensity, which tends to manifest most clearly at the greatest intensities. The Saffir-Simpson scale for categorizing damage based on the wind intensity of TCs was introduced in the early 1970s and remains the most commonly used metric for public communication of the level of wind hazard that a TC poses. Because the scale is open-ended and does not extend beyond category 5 (70 m/s windspeed or greater), the level of wind hazard conveyed by the scale remains constant regardless of how far the intensity extends beyond 70 m/s. This may be considered a weakness of the scale, particularly considering that the destructive potential of the wind increases exponentially. Here, we consider how this weakness becomes amplified in a warming world by elucidating the past and future increases of peak wind speeds in the most intense TCs. A simple extrapolation of the Saffir-Simpson scale is used to define a hypothetical category 6, and we describe the frequency of TCs, both past and projected under global warming, that would fall under this category. We find that a number of recent storms have already achieved this hypothetical category 6 intensity and based on multiple independent lines of evidence examining the highest simulated and potential peak wind speeds, more such storms are projected as the climate continues to warm.

Mapping individual aspects of bilingual experience to adaptations in brain structure.

Individual differences in using multiple languages are thought to differentially affect brain structure and function. The present study assessed the neuroanatomical predictions of an emerging theory, the Unifying the Bilingual Experience Trajectories framework, which provides the most comprehensive set of predictions of how individual differences in bilingual experiences lead to specific neural and cognitive adaptations. A total of 140 young adults with variable language experiences were scanned using magnetic resonance imaging and completed demographic questionnaires. Brain structure measures implicated in predictions of the Unifying the Bilingual Experience Trajectories model were extracted and regressed against the model's experiential factors. Consistent with the model's predictions, greater intensity and diversity of bilingual language use resulted in changes in gray matter volume in cortical regions involved in executive control (including inferior frontal gyrus, middle temporal gyrus, angular gyrus, and medial frontal gyrus), indicating adaptations toward handling increased executive control demands. Conversely, duration of bilingual engagement resulted in changes within white matter microstructure (bilateral superior longitudinal fasciculus) and increases in subcortical gray matter (left caudate), indicative of adaptations toward increased efficiency of control. Overall, this research enhances our understanding of how bilingual experiences influence brain structure and provides the first direct empirical evidence for the predictions made by the Unifying the Bilingual Experience Trajectories framework.

Analysis of polarization features of human breast cancer tissue by Mueller matrix visualization.

Breast cancer ranks second in the world in terms of the number of women diagnosed. Effective methods for its early-stage detection are critical for facilitating timely intervention and lowering the mortality rate. Polarimetry provides much useful information on the structural properties of breast cancer tissue samples and is a valuable diagnostic tool. The present study classifies human breast tissue samples as healthy or cancerous utilizing a surface-illuminated backscatter polarization imaging technique. The viability of the proposed approach is demonstrated using 95 breast tissue samples, including 35 healthy samples, 20 benign cancer samples, 20 grade-2 malignant samples, and 20 grade-3 malignant samples. The observation results reveal that element in the Mueller matrix of the healthy samples has a deeper color and greater intensity than that in the breast cancer samples. Conversely, element shows a lighter color and reduced intensity. Finally, element has a darker color in the healthy samples than in the cancer samples. The analysis of variance test results and frequency distribution histograms confirm that elements , , and provide an effective means of detecting and classifying human breast tissue samples. Overall, the results indicate that surface-illuminated backscatter polarization imaging has significant potential as an assistive tool for breast cancer diagnosis and classification.

Global synthesis of effects and feedbacks from artificial reefs on socioecological systems in recreational fisheries

AbstractArtificial reefs have been widely deployed with the intention of increasing fish habitat, enhancing recreational fishery opportunities and providing socio‐economic benefits to surrounding communities. Substantial work has been done to understand the ecology of artificial reefs but the efficacy of artificial reefs as a management tool hinges on socioecological feedbacks that are not well understood. Socioecological feedbacks are difficult to discern because they depend on multiple and complex interactions between fish, fishers, managers and habitats. To better understand the net effects of artificial reefs on recreational fisheries, we conducted a literature review to catalogue effects and feedbacks of artificial reefs. Our global synthesis revealed that artificial reefs may result in a net negative effect on fish populations, at least in the short‐term, as catch‐driven effects bolstering socio‐economic objectives occur more often or at greater intensities than positive biological effects. We have highlighted important effects of artificial reefs and feedbacks that need to be accounted for when considering their deployment in fishery management. There may be unintended consequences if biological benefits from habitat‐to‐fish and fish‐to‐fish feedbacks are outweighed by population losses due to greater socio‐economic benefits from fish‐to‐fisher feedbacks. Taken in concert with their semi‐permanent nature and apparent popularity with stakeholders, a view emerges of artificial reefs possibly functioning as a ‘social‐ecological trap’. This work emphasizes the need for robust assessments of the effects of artificial reefs, as well as more formal decision science approaches for implementing of these structures.

Hand-Use Preferences for Reaching and Object Exploration in Children with Impaired Upper Extremity Functioning: The Role of Environmental Affordances

Infants and young children with weakened or impaired upper extremity functioning often develop a strong hand-use “preference” for reaching and object manipulation. While “preferring” their stronger hand, they often partially or completely ignore their “non-preferred” hand. Such manual lateralization might impede complex object exploration, which would negatively affect children’s cognitive development. The question is whether environmental affordances would significantly affect children’s manifested hand-use “preferences” by promoting the use of the “non-preferred” hand. The current sample included 17 children (5 males; 13.9 ± 8.7 months at baseline) with arthrogryposis multiplex congenita (arthrogryposis). The reaching and object exploration of the children were evaluated longitudinally across a 6-month period with and without the Playskin LiftTM exoskeletal garment (Playskin). Results showed that the use of the Playskin increased both unimanual and bimanual object contact. Also, when anti-gravity support was provided to the arms by the Playskin, children significantly increased the use of their non-preferred hand, which correlated with improved quality of object play—more bimanual object interaction and greater intensity, variability, and complexity of exploration. These findings suggest that hand-use “preference” in children with arthrogryposis is quite malleable during early development. It is likely that children with impaired upper extremity functioning do not “prefer” to use a particular hand but, rather, cannot afford using both hands due to their limited muscular or manual abilities. Importantly, environmental affordances (i.e., anti-gravity support for the arms) might significantly affect the early development of manual lateralization, with potential implications for children’s quality of object exploration and future cognitive development.

Energy poverty and functional disability nexus: Empirical evidence from Ghana

Energy poverty in developing low- and middle-income economies continues to persist, especially in sub-Saharan Africa. However, empirical studies that examine the channels through which it impacts well-being indicators remain scanty. The growing occurrence of functional disabilities in hearing, vision, mobility, communication, self-care, and cognition, therefore, provides an untapped means of examining the energy poverty and well-being nexus. Against this backdrop, this study uses data from the 10 % microdata of Ghana's recent Population and Housing Census to analyze a modified multidimensional energy poverty for 835,695 households. Underpinned by the capability framework, the structural equation modeling technique was employed to examine the nexus between energy poverty and functional disability. The findings reveal significant positive impact of energy poverty on functional disability and notably, geographical, gender, and age-group differences. Also, a high incidence of modified multidimensional energy poverty was found with greater intensity among rural residents, savanna zone inhabitants, elderly people, and female-headed households. These findings reveal the policy relevance and urgency to alleviate energy poverty to check functional decline and promote household well-being.

When crises meet grand environmental challenges: Navigating intertemporal tensions in European manufacturing family firms

ABSTRACT The grand environmental challenge of climate change represents one of the key ongoing, long-term obstacles for organizations. When interrupted by short-term exogenous crises like the COVID-19 pandemic and the shock of the Ukrainian war, the urgency of addressing this grand challenge becomes more pressing, albeit more challenging. While family firms as long-term oriented organizations might generally be well equipped to tackle climate change, we know surprisingly little on how they simultaneously experience and navigate the long-term horizon of grand environmental challenges and the short-term pressures of exogenous crises. Drawing on research around long-term orientation (LTO) and a growing stream investigating intertemporal tensions, we investigate this question building on 41 interviews with nine family firms in the context of the European manufacturing industry. Applying an abductive approach, our findings unveil three intertemporal tensions that unfold when short-term and long-term objectives collide. Besides, we show that family firms, due to their LTO, perceive these tensions with a greater intensity. Navigating the perceived tensions, we identify two mechanisms employed by family firms that mitigate the negative implications of LTO. Doing so, we contribute to extant research on grand challenges and cast light on the downsides of LTO in family firms.

Association between genomic daughter pregnancy rate and expected milk production on the resumption of estrus behavior in Holstein cattle

The objective of this observational study was to evaluate estrous expression at the first estrus occurring between 7 to 30 d in milk (DIM), as detected by an automated activity monitor (AAM), and its association with genomic daughter pregnancy rate (GDPR) and genomic expected milk production (GEM) in lactating dairy cows. A total of 4,119 lactations from 2,602 Holstein cows were included. Cows were enrolled as first lactation (n = 1,168), second lactation (n = 1,525) and third and greater lactation (n = 1,426). Hair samples were collected from the tail switch, and cows were genotyped using an SNP platform (Clarifide, Zoetis, São Paulo, SP, Brazil). Postpartum cows were examined daily by the farm personnel from calving until 10 DIM. Calving was classified as assisted (forced calf extraction) and unassisted (normal calving). Retained fetal membranes (RFM), hyperketonemia (KET), and left displaced abomasum (LDA) were also recorded. Mean GDPR (± SD) was -0.29 ± 1.4, and the intensity and duration of the first estrus event was 15.9 ± 13.1 x-factor (intensity unit measurement) and 11.1 ± 3.8 h, respectively. Cows that had greater GDPR had greater intensity and longer duration of estrus at the alert, independent of parity. Overall resumption of estrous expression, between 7 to 30 DIM, was 41.2% (1,695/4,119), where 58.8% (2,424/4,119) did not have an estrus event, 31.0% (1,274/4,119) of cows had one event of estrus, and 10.2% (421/4,119) of cows had 2 or more events of estrus early postpartum. Mean DIM (± SD) at first estrus event, detected by the AAM, was 19.4 ± 4.4 d. Days in milk at first event for cows with one event was 20.7 ± 1.6 d and 15.9 ± 3.1 d for cows with 2 or more events of estrus. First lactation cows were more likely to have an estrus event early postpartum when compared with second and third and greater lactation cows (45.2 ± 1.4% [530/1168] vs. 41.6 ± 1.3% [636/1525] vs. 37.2 ± 1.3% [529/1426], respectively). There was an interaction of parity and GDPR on the proportion of cows demonstrating an early postpartum estrus. There was no difference in the proportion of cows with an early postpartum estrus between those with assisted or unassisted calving, RFM, or LDA. However, cows that had KET were less likely to have an alert early postpartum when compared with cows that did not have KET. Mean genomic expected milk production (± SD) was 256.8 ± 600.1 kg. There was no interaction between GEM and parity on estrous expression (i.e., intensity and duration). There was no interaction between GEM and GDPR on the proportion of estrus early postpartum.

Sedimentary Circumstances and Physiographic Sites Impact on the Morphological Properties of Feldspar Minerals of Iraqi Soils

The current research aimed to investigate the effect of sedimentary conditions, physiographic locations, proximity, and distance from the source on the morphological characteristics of feldspar minerals diagnosed by Scanning Electron Microscope (SEM) for some selected soils from northern and southern Iraq. The results of SEM present the emergence of a series of surface changes, corrosion, and the absence of healthy surfaces on the surfaces of orthoclase metal. It is dominated by roundness or sphericity, with the polishing of the metal surfaces coinciding with the phenomenon of roundness and sphericity. The edges of the orthoclase mineral were less affected due to being transported over long distances with transported river deposits. The presence of long lines indicates that the metal is subject to weathering and change. One of the most critical manifestations of change occurring on the surfaces of feldspars is the emergence of long parallel lines, which are called linear parallels, which reflect the severity of weathering to which the feldspar minerals were subjected. The morphological characteristics of the surfaces of the mineral microcline appeared under the SEM similar to those shown by the surfaces of the mineral orthoclase with clarity of the phenomenon of linear parallelism and a decrease in the phenomena of sphericity and polishing compared to the surfaces of the mineral orthoclase, which is less stable and resistant to weathering than the microcline. There was a phenomenon of accumulated plates on the surface of the metal, with the edges of the metal being subjected to weathering processes with greater intensity than the surface areas, despite the expansion of the surface area of the metal particles. The appearance of plagioclase of albite type and the edges of its particles were less affected by the weathering processes compared to its surfaces. The reason is attributed to the fact that the edges area is more susceptible to erosion and grinding during transport. This discrepancy in the morphological characteristics of feldspar minerals is attributed to their influence on the processes of weathering, transport, and sedimentation in the soils of the study areas and to the variation in their physiographic locations and their distance and proximity to the Iraqi-Iranian border strip in southern Iraq within the sedimentary plain affected by sediments coming from the heights of Iran in addition to being affected by the sediments of the Tigris River.

Variation in the Basic Density of Woods Produced in the Brazilian Semiarid Region Subjected to Different Irrigation Regimes

The present work aimed to evaluate the wood of fourteen genetic materials (nine species, between native and exotic, and five clones of Eucalyptus) cultivated under two post-planting irrigation regimes in the Brazilian semiarid region. For each genotype, six trees (11 years old) were selected and subjected to two initial irrigation regimes (up to 12 months and up to 36 months) after planting. Discs of different stem heights were taken: 0% (base), breast height (DBH), 20%, 40%, 60%, 80%, and 100%. Samples were extracted along the radial axis of each disk at three regions (the pith-adjacent region, intermediate region, and bark-adjacent region). Samples were subsequently saturated in water to determine their density via the water displacement method. The irrigation systems caused changes in the pattern of radial and longitudinal variation in the clones regarding the proportion of woody material in the stem. Among the native species, Angico stood out with a high density and little juvenile wood, and Pau d’arco, with a low density and a high rate of juvenile wood. Among the exotic species, Nim presented a high density and a low rate of juvenile wood, and Chichá presented a high rate of juvenile wood and a low density. In the Eucalyptus hybrids, VE38 stood out with a high density. Overall, there was an influence from irrigation management, observed with greater intensity in exotic species for Mahogany and Acacia and for the VE41 and AEC1528 clones of Eucalyptus. The values of basic densities in the trees varied from 0.35 to 0.85 g·cm−3. There was good adaptation of native and exotic species and clones to the planting area in the Semiarid region.

Experimental and computational study on xylan pyrolysis: The pyrolysis mechanism of main branched monosaccharides

The high percentage of branched units with different structures leads to the complex pyrolysis chemistry and product distribution of hemicellulose. In this study, four main branched monosaccharides, i.e., arabinose (Ara), galactose (Gal), galacturonic acid (GacA), and glucuronic acid (GlcA) were employed as typical xylan-based hemicellulose model compounds. The pyrolysis behaviors and mechanisms of these monosaccharides were deeply explored by the combination of pyrolysis experiments and density functional theory (DFT) calculations. Particularly, the roles of structural differences of these monosaccharides were carefully analyzed. Due to the uronic acid group, GacA and GlcA were easier to decompose, having two weightloss peaks with close intensity, and the release of CO2 had greater intensity than Ara and Gal pyrolysis at low temperatures. GlcA with the equatorial hydroxyl group can undergo a special CC bond breaking reaction to depart the C6 uronic acid group to release HCOOH. The fast pyrolysis of these monosaccharides obtained similar product species but distinct relative contents. The structure of an uncertain hydromethyl-furnaose product was identified as 5-(hydroxymethyl)furan-3(2H)-one (5-HMFO) by combined DFT calculations and experimental results. The findings of this work are beneficial to gain a deep understanding of the pyrolysis chemistry of hemicellulose, especially the role of different branches.